May 15, 2021 9:00am Researchers found that taking less than 10 minutes to seal the appendage could reduce the number of ischemic strokes by at least a third. (Pixabay) As long as surgeons have a patient under anesthesia for one heart procedure, they may as well make it two—and according to a new study, the benefits in preventing future strokes could last a lifetime. Researchers examined whether making a quick detour during surgery to close off the left atrial appendage—a small pouch in the wall of the heart muscle, where it’s believed blood can pool and form dangerous clots—could help reduce the overall risk of stroke in patients with atrial fibrillation that isn’t caused by a heart valve.